Whether you’re thinking about taking your first trip to the dark web or already know your way around, there’s a very simple thing you need avoid doing. Don’t ever go full screen.
The dark web is a place where you need a specialised browser. The most well known is Tor, but there are other ones too.
The entire point of the dark web is anonymity. While this can be for nefarious purposes, that’s definitely not always the case. It can also offer a somewhat safer place for people to share information – such as journalists and whistleblowers.
It’s also a place where people who value privacy in general can go about their business.
But you’re not just automatically anonymous. There’s plenty you can do to give your identity and location away. Even seemingly small and innocuous things.
If you’ve ever used Tor, you may notice that it does not open in full screen by default. It opens in a smaller size and there’s a good reason for that.
Why full screen on the dark web isn’t recommended
Maximising a browser window means that a website can work out the size of your monitor. This may seem like no big deal, but if someone changes the default browser size it makes their session stand out, leaving them open to being tracked or identified.
Browser size can be identifying data, particularly if there is other information or data that the site can utilise.
This is problematic when you’re trying to be anonymous.
Manually resizing Tor to another random size is also an issue as you’re then creating a very unique fingerprint, particularly if you keep that setting between sessions.
Tor flags this itself on its website.
“Tor Browser in its default mode is starting with a content window rounded to a multiple of 200px x 100px to prevent fingerprinting the screen dimensions. The strategy here is to put all users in a couple of buckets to make it harder to single them out,” the website reads.
“That works so far until users start to resize their windows (e.g. by maximizing them or going into full screen mode)”
It’s worth noting that this isn’t just a problem on the dark web. Browser sizing can be used as an identifier on the regular web as well. But when we give so much of our info up so freely in the front-facing web on the daily, it doesn’t seem like as big a problem.
Is there a way around it?
Tor itself implemented a solution that Mozilla first introduced in 2019. It’s called Letterboxing and essentially adds thin margins to the browser window to make it pretty close to the screen size the user wants.
This still protects their anonymity because they can be singled out for their screen dimensions.
“In simple words, this technique makes groups of users of certain screen sizes and this makes it harder to single out users on basis of screen size, as many users will have same screen size,” the Tor website says.